Staging: sm7xx: add a new framebuffer driver

Yeeloong netbook has a sm712 video card, need this driver, but it is not
ready to upstream yet, so, go to drivers/staing at first.

This source code is originally from Silicon Motion Technology Corp, and
maintained at http://dev.lemote.com/code/linux_loongson for YeeLoong
netbook. I have done a lot of cleanups for it and merged it into my git
repository at http://dev.lemote.com/code/rt4ls.

Thanks to Simon for testing it on a little-endian x86 platform.

Thanks to Olivier Croset <olivier.croset@actis-computer.com> for
reporting the problem about __BIG_ENDIAN compiling problem and send a
relative patch.

The suspend/resume and blank support are contributed by Jason from
Silicon Motion Technology.

Tested-by: Simon Braunschmidt <sbraun@emlix.com>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/sm7xx/TODO b/drivers/staging/sm7xx/TODO
new file mode 100644
index 0000000..1f61f5e
--- /dev/null
+++ b/drivers/staging/sm7xx/TODO
@@ -0,0 +1,10 @@
+TODO:
+- Dual head support
+- use kernel coding style
+- checkpatch.pl clean
+- refine the code and remove unused code
+- use kernel framebuffer mode setting instead of hard code
+- move it to drivers/video/sm7xx/ or make it be drivers/video/sm7xxfb.c
+
+Please send any patches to Greg Kroah-Hartman <greg@kroah.com> and
+Teddy Wang <teddy.wang@siliconmotion.com.cn>.